In a bayonet-type fuse and fuseholder assembly, there are a tubular fuseholder housing of electrical insulating material and two sets of generally-stationary spring-loaded contacts mounted on the housing in locations spaced apart along the length of housing. Within the fuseholder housing there is a removable fuse cartridge enclosing a fuse link and having terminal contacts at its opposite ends for respectively engaging the stationary contacts to establish a circuit through the fuse link between the stationary contacts. The fuse cartridge is mounted on the distal end of an insulating operating rod that is also located within the fuseholder housing and is operable to effect a disconnect operation that separates the terminal contacts of the fuse cartridge from the stationary contacts that normally engage them, thereby developing arcs between the separated contacts under load-break conditions.
These arcs, being very hot, tend to produce arc erosion of the contacts, burning of the springs loading the stationary contacts, and carbonization of nearby insulating material, thus limiting the number of disconnecting operations that can be effected before it becomes necessary to replace one or more of these components in order to prevent a failure. A type of failure that can occur is one resulting from carbonization of the internal surface of the fusehold housing. Such carbonization can lead to an arc-over between the generally stationary contacts when the fuse is removed from its normal position between these contacts.
An object of my invention is to reduce the damaging effect of the arcs and thereby increase the number of disconnecting operations that can be effected under load-break conditions without a failure.